cam_pos      = [0.68125, 1.40962, -0.0876588]';
cam_dir      = [-0.898225, -0.243768, -0.365744]';
cam_up       = [-0.168391, 0.959477, -0.225941]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.53998, 0.188006, 1.20082]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;